title: Electron trajectory selection for high harmonic generation inside a short hollow fiber.
abstract: The 19th harmonic beam divergences from a Ti:sapphire laser generated using a gas jet and 10-mm-long hollow fibers with bore diameters of 300 and 200 μm were investigated. The beam quality factor M(2) of the harmonic beam generated in a 300-μm hollow fiber was found to be better than the gas jet using the phase match including the atomic dipole phase induced by the short trajectory. On the other hand, a 200-μm hollow fiber was found to generate a more divergent beam with a larger M(2) because of the long trajectory. The electron trajectory contributing to high harmonic generation was selected using the phase-matching process inside a short hollow fiber.
authors.forename: Hironori
authors.initials: H
authors.lastname: Igarashi
authors.forename: Ayumu
authors.initials: A
authors.lastname: Makida
authors.forename: Taro
authors.initials: T
authors.lastname: Sekikawa